Genovis Products for Antibody Fragmentation


FabRICATOR® is a unique proteolytic enzyme that cleaves the IgG just below the hinge region, thereby generating an intact F(ab′)2 fragment and a Fc fragment. The enzyme is a modified cysteine protease first isolated from Streptococcus pyogenes. The scientific name of the enzyme is IdeS (immunoglobulin degrading enzyme), which has a biological role of circumventing the host defense.

Advantages of using FabRICATOR for F(ab′)2 or Fab′ production

  • Fast - IgG cleaved within 30 minutes
  • No optimization - works right out of the box
  • Homogenous - cleavage position is exactly the same in each generated fragment
  • Gentle method - reaction is carried out at physiological pH with no negative effect on immunoreactivity of the generated fragments

Antibodies compatible with FabRICATOR enzyme:
Human IgG, Humanized IgG, Chimeric IgG, Monkey, Rabbit, Sheep, Mouse IgG2a, Mouse IgG3

Fab and F(ab′)2 antibody fragments are used in many applications or assays where the presence of the Fc region may cause problems. If antibodies are used for staining of a specific target in tissues like spleen, lymph or in peripheral blood preparations, cells with Fc receptors (macrophages, monocytes, natural killer cells and B lymphocytes) can bind to the Fc region of the antibody and cause background staining in areas that do not contain any antigen.
Fab and F(ab′)2 fragments are also desirable for staining or binding to cell preparations in the presence of plasma since they cannot bind to complement, which would lyse the cells. The divalency of the F(ab′)2 fragment enables it to cross-link antigens and hence makes it useful for rosetting, cellular aggregation and precipitation assays.

The FragIT kit is the most convenient and economical way to produce pure F(ab′)2 or Fab′ from IgG. The FragIT kit consists of two spin columns, one for the actual fragmentation and a second spin column to collect the Fc-fragments. This solution offers many advantages over existing technologies:
  • Speed - the time for completion is very fast, usually less than one hour even for first-time users.
  • Yield - usually more than 95% of starting material is recovered.
  • Purity - the included affinity separation column binds selectively to the Fc fragment, leaving very pure F(ab′)2 fragments in the flow-through.
  • Immuno reactivity - gentle handling of the fragments throughout the procedure minimizes reduction of immunoreactivity.
  • Cost - highly cost-effective method due to high yield and the excellent quality of the fragments generated. The short handling time increases the value of this fragmentation solution for the end user.

FragIT microspin columns allow for easy and quick fragmentation of IgG into F(ab’)2 and Fc fragment. FragIT microspin columns come prefilled with FabRICATOR enzyme immobilized on agarose. Fragmentation of IgG is typically associated with low yield, heterogeneity of produced fragments and a cumbersome and time-consuming process. All these shortcomings can now be solved using FragIT microspin columns for fragmentation of up to 0.5 mg IgG in less than 30 minutes.

FabRICATOR Specificty for IgG Subtypes Verified in:
Rapid LC-MS screening for IgG Fc modifications and allelic variants in blood. Goetze, A. M., et al. Mol. Immunol. 49, 338-352, (2011)